全文获取类型
收费全文 | 370篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 29篇 |
环保管理 | 35篇 |
综合类 | 46篇 |
基础理论 | 81篇 |
环境理论 | 1篇 |
污染及防治 | 98篇 |
评价与监测 | 63篇 |
社会与环境 | 10篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 7篇 |
2022年 | 9篇 |
2021年 | 7篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 6篇 |
2017年 | 11篇 |
2016年 | 15篇 |
2015年 | 14篇 |
2014年 | 28篇 |
2013年 | 54篇 |
2012年 | 13篇 |
2011年 | 16篇 |
2010年 | 25篇 |
2009年 | 22篇 |
2008年 | 21篇 |
2007年 | 17篇 |
2006年 | 18篇 |
2005年 | 15篇 |
2004年 | 10篇 |
2003年 | 11篇 |
2002年 | 6篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1960年 | 1篇 |
1943年 | 1篇 |
1942年 | 1篇 |
1940年 | 1篇 |
1937年 | 1篇 |
1936年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有376条查询结果,搜索用时 15 毫秒
71.
The selection of new settlement areas and the construction of safe buildings, as well as rendering built‐up areas safe, are of great importance in mitigating the damage caused by natural disasters. Most cities in Turkey are unprepared for natural hazards. In this paper, Çanakkale, located in a first‐degree seismic zone and sprawled around the Sartçay Delta, is examined in terms of its physical vulnerability to natural hazards. Residential areas are analysed using GIS (geographic information system) and remote‐sensing technologies in relation to selected indicators. Residential areas of the city are divided into zones according to an evaluation of geological characteristics, the built‐up area's features, and urban infrastructure, and four risk zones are determined. The results of the analysis show that the areas of the city suitable for housing are very limited. In addition, the historical centre and the housing areas near Sartçay stream are shown to be most problematic in terms of natural disasters and sustainability. 相似文献
72.
The fatty acid (FA) composition was determined in 14 species of marine macroalgae belonging to the Chlorophyta, Phaeophyta and Rhodophyta, which were collected from ?ile in the Black Sea and Kepez in the Dardanelles. Generally, polyunsaturated FAs and monounsaturated FAs were major components (50–77%). Total saturated FAs ranged from 22% to 50%, with 16?:?0 as the most abundant saturate (32–38%). Two samples of Cystoseira barbata collected from a different station had some differences from each other in their contents of 18?:?2n-6 and 18?:?3n-3 and in the 18?:?2n-6/20?:?4n-6 ratios. Green algal species had a significantly higher proportion of unsaturated FAs and a significantly lower proportion of saturated FAs than the red and brown algae. The amount of n-3 FAs was significantly higher in Ulva rigita, Chaetomorpha linum, Enteromorpha linza and Gracilaria verrucosa (8.88, 6.44, 5.31 and 5.24, respectively). 相似文献
73.
The exhaust emissions from two heavy duty diesel vehicles running on eight different fuel compositions were investigated regarding their content of high molecular weight (≥ C12) aliphatic/ olefinic hydrocarbons. It was concluded that the emitted amount of semi‐volatile associated aliphatic hydrocarbons (range C12‐C22) depend on the fuel used in the engines and that these emissions mainly consisted of uncombusted fuel components. It was also found that uncombusted engine lubrication oil was the main constituent of the emitted particulate associated aliphatic hydrocarbons (C17‐C40). These constituted between 58% and 95% of the total emissions of the high molecular weight aliphatic compounds. Emission factors for the total of high molecular aliphatic hydrocarbons (C12‐C40) were demonstrated to be in the range of 15–100 mg/km. Some individual aliphatic hydrocarbons with cocarcinogenic effects were identified and quantified in both particulate and semi‐volatile phases of the exhaust. Multivariate data analysis was used to investigate the relationship between fuel parameters and emission of semi‐volatile aliphatic emission. 相似文献
74.
Şerif Hepcan Adnan Kaplan Bülent Özkan Erhan Vecdi Küçükerbaş Emine Malkoç Yiğit Hatice Sönmez Türel 《国际发展与全球生态学杂志》2013,20(5):375-389
This study examines the possibility of designating and implementing a citywide public space network, constituted of randomly dispersed and not interrelated public spaces and greenways across the city of Mu?la. Although Mu?la is a major coastal province, with worldwide tourism districts, the city centre falls behind other settlements in terms of quality of social life, physical layout, economic investment and tourism revenue. In 2001, the local government commissioned the Department of Landscape Architecture of Ege University to prepare a comprehensive master plan towards achieving a corporate public space network, as well as development strategies to ameliorate the previous failures. The master plan developed a blueprint for the citywide network and addressed each existing or potential public space and greenway as integrated components of the network. The process involved short-, medium- and long-term action from the local government to achieve the physical layout and efficiently implement phases of the network. As a guide for other small or medium urban settlements in Turkey, a model proposal was derived from the study to address formulation, implementation, and management of the network in order to create a sustainable urban development. 相似文献
75.
Tommy Kristensen Anders Isberg Nielsen Anders Isak J?rgensen Kim N. Mouritsen Henrik Glenner Jens T. Christensen J?rgen Lützen Jens T. H?eg 《Marine Biology》2012,159(9):2015-2023
Male crabs infected by parasitic barnacles (Rhizocephala) are known to be morphologically feminized. Here, we investigate morphological chances in green crabs, Carcinus maenas, induced by the parasitic barnacle Sacculina carcini. Infected males acquire a broader, longer and segmented abdomen, fringed with marginal setae. Copulatory appendages and pereopods are reduced in length, and the chelae become smaller. The feminization show great individual variation. Males with scars from lost externae, the parasites reproductive organ situated under the abdomen, are less modified than males carrying an externa, and the feminization is more pronounced in smaller than in larger males. No super-feminization is evident in female crabs that remain morphologically unaffected by infection. The protective value of a parasitically induced enlargement of the male abdomen may constitute an adaptation that increases parasite longevity. The additional effects on male morphology are viewed as pleiotropic side effects of the main adaptive value of enlarging the abdomen. 相似文献
76.
Spherical TiO2 nanoparticles (npTiO2) were prepared by controlled hydrolysis of tetraethoxy orthotitanate under a nitrogen atmosphere. ZnO nanoparticles (npZnO) were prepared using hydrothermal methods. The crystal structure, chemical, thermal and morphological properties of npZnO and npTiO2 were characterised using Fourier Transform Infrared Spectrometer, enery-dispersive X-ray spectroscopy, X-ray diffraction, and scanning electron microscope techniques. The short- and long-term experiments were started with neonates taken from the same culture and laboratory condition. In the acute experiments, npTiO2, npZnO, and cocktail concentrations were applied. 96h-LC50 values were 1.8, 0.7, and 0.1?mg?L?1, respectively (p?<?.05). For the chronic experiments, different npTiO2 concentrations were performed. 21d-LC50 value was 1.0?mgL?1 (p?<?.05). Morphometry became progressively worse in concentrations of more than 1?mgL?1 npTiO2. Neonate and young individuals were more sensitive to death because of their low tolerance. This result was affected by population progeny and growth rates (p?<?.05). While control and 0.5?mgL?1 npTiO2 groups were determined as growing population, 1.5 and 2?mgL?1 npTiO2 groups had decreased population size as R0 values. Consequently, the relationships between nanoparticle accumulation within Daphnia magna and its population structure and body morphometry for each concentration were important indicators. Its tolerance level to nanoparticles under laboratory conditions reflected its replacement and behaviour in the ecosystem. 相似文献
77.
Physical and biological disturbances are ecological processes affecting patterns in biodiversity at a range of scales in a variety of terrestrial and aquatic systems. Theoretical and empirical evidence suggest that effects of disturbance on diversity differ qualitatively and quantitatively, depending on levels of productivity (e.g., the dynamic equilibrium model). In this study we contrasted the interactive effects between physical disturbance and productivity to those between biological disturbance and productivity. Furthermore, to evaluate how these effects varied among different components of marine hard-substratum assemblages, analyses were done separately on algal and invertebrate richness, as well as richness of the whole assemblage. Physical disturbance (wave action) was simulated at five distinct frequencies, while biological disturbance (grazing periwinkles) was manipulated as present or absent, and productivity was manipulated as high or ambient. Uni- and multivariate analyses both showed significant effects of physical disturbance and interactive effects between biological disturbance and productivity on the composition of assemblages and total species richness. Algal richness was significantly affected by productivity and biological disturbance, whereas invertebrate richness was affected by physical disturbance only. Thus, we show, for the first time, that biological disturbance and physical disturbance interact differently with productivity, because these two types of disturbances affect different components of assemblages. These patterns might be explained by differences in the distribution (i.e., press vs. pulse) and degree of selectivity between disturbances. Because different types of disturbance can affect different components of assemblages, general ecological models will benefit from using natural diverse communities, and studies concerned with particular subsets of assemblages may be misleading. In conclusion, this study shows that the outcome of experiments on effects of disturbance and productivity on diversity is greatly influenced by the composition of the assemblage under study, as well as on the type of disturbance that is used as an experimental treatment. 相似文献
78.
Michael Tobler Dennis Hasselquist Henrik G. Smith Maria I. Sandell 《Behavioral ecology and sociobiology》2010,64(5):717-727
Hormone-mediated maternal effects play an important role in the formation of a differentiated phenotype. They have been shown
to influence a wide array of offspring traits, both early in life and in adulthood. One important offspring trait that is
under the influence of maternal androgens is the immune system. In birds, a growing number of studies show that yolk androgens
modulate immune function during the chick stage. However, there is a lack of knowledge regarding long-term effects of prenatal
androgens on offspring immunity. In this study, we therefore investigated the influence of prenatal testosterone (T) on several
measures of immunity in fledgling and adult zebra finches (Taeniopygia guttata). Cell-mediated immune response (towards phytohaemagglutinin, PHA) of fledglings hatching from control eggs was negatively
related to brood size, whereas there was no such association for fledglings hatching from eggs with experimentally elevated
T levels (T fledglings). Male control fledglings showed reduced mass gain compared to female control fledglings within 24 h
after the PHA injection. This pattern was reversed in T fledglings. Total antibody levels in fledglings were not affected
by egg treatment. Neither cell-mediated immunity nor total antibody levels in sexually mature zebra finches were influenced
by egg treatment. However, there was an immuno-enhancing effect of elevated egg T on both primary and secondary humoral immune
responses toward diphtheria and tetanus antigens in ca 5 and 7 month old zebra finches. In addition, the covariation between
different immune components differed between T and control offspring, suggesting that egg treatment may have altered the potential
trade-offs between different parts of the immune system. Our results suggest that prenatal androgens could be an important
factor contributing to individual variation in immune function even in adulthood. 相似文献
79.
Functional response diversity is defined as the diversity of responses to environmental change among species that contribute to the same ecosystem function. Because different ecological processes dominate on different spatial and temporal scales, response diversity is likely to be scale dependent. Using three extensive data sets on seabirds, pelagic fish, and zooplankton, we investigate the strength and diversity in the response of seabirds to prey in the North Sea over three scales of ecological organization. Two-stage analyses were used to partition the variance in the abundance of predators and prey among the different scales of investigation: variation from year to year, variation among habitats, and variation on the local patch scale. On the year-to-year scale, we found a strong and synchronous response of seabirds to the abundance of prey, resulting in low response diversity. Conversely, as different seabird species were found in habitats dominated by different prey species, we found a high diversity in the response of seabirds to prey on the habitat scale. Finally, on the local patch scale, seabirds were organized in multispecies patches. These patches were weakly associated with patches of prey, resulting in a weak response strength and a low response diversity. We suggest that ecological similarities among seabird species resulted in low response diversity on the year-to-year scale. On the habitat scale, we suggest that high response diversity was due to interspecific competition and niche segregation among seabird species. On the local patch scale, we suggest that facilitation with respect to the detection and accessibility of prey patches resulted in overlapping distribution of seabirds but weak associations with prey. The observed scale dependencies in response strength and diversity have implications for how the seabird community will respond to different environmental disturbances. 相似文献
80.
Permeable biobarrier systems (PBSs) are being recognized as low‐cost passive bioremediation technologies for chlorinated organic contamination. This innovative technology can play a crucial and effective role in site restorations. Laboratory‐scale experiments were conducted to investigate the biodegradation of trichloroethylene (TCE) to ethylene in shallow groundwater through the use of a PBS enhanced by bioaugmentation at the U.S. Department of Energy's Savannah River Site (SRS). Two composts and two plant amendments, eucalyptus mulch (EM) and corncobs (CC), were examined for their effectiveness at creating and maintaining conditions suitable for TCE anaerobic dechlorination. These materials were evaluated for their (1) nutrient and organic carbon content, (2) TCE sorption characteristics, and (3) longevity of release of nutrients and soluble carbon in groundwater to support TCE dechlorination. Native bacteria in the columns had the ability to convert TCE to dichloroethenes (DCEs); however, the inoculation with the TCE‐degrading culture greatly increased the rate of biodegradation. This caused a significant increase in by‐product concentration, mostly in the form of DCEs and vinyl chloride (VC) followed by a slow degradation to ethylene. Of the tested amendments, eucalyptus mulch was the most effective at supporting the reductive dechlorination of TCE. Corncobs created a very acidic condition in the column that inhibited dechlorination. © 2007 Wiley Periodicals, Inc. 相似文献